Unfortunately, that doesn't work

my @words = qw[ the quick brown fox ];

foreach (@words) { ucfirst($_); };
Useless use of ucfirst in void context at ...
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It would have to be

foreach (@words) { $_ = ucfirst($_); }
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Or, more simple

$_ = ucfirst for @words;

print for @words;
The
Quick
Brown
Fox
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